The report is the latest in a series, begun in 1997, produced under the BTO's partnership with the Joint Nature Conservation Committee (on behalf of Natural England, Scottish Natural Heritage, the Countryside Council for Wales, and the Council for Nature Conservation and the Countryside) as part of its programme of research into nature conservation.
Only the first two reports were published on paper, with subsequent ones being produced solely as web documents. A complete list of all the previous reports and links to those published online can be found here. The first 12 reports were titled Breeding Birds in the Wider Countryside: their conservation status, with 'birdtrends' as the link to the web pages and 'wider countryside report' as their informal title. 'Bird Trends' is now the informal title of the report, matching the web link.
The current report in the series is used by conservation practitioners as a ready reference to changes in status among breeding birds in the UK. By publishing it on the BTO website, we aim to make it available to a much wider audience, especially to BTO members and the general birdwatching public. We hope that it also provides a useful resource for schools, colleges and universities, the media, ecological consultants, decision-makers, local government, and the more general world of industry and commerce. In summary, its aims are:
- To provide, to as wide a readership as possible, a species-by-species overview of the trends in breeding population and reproductive success of birds covered by BTO monitoring schemes since the 1960s, at the UK or UK-country scale.
- To provide warning alerts to JNCC and Country Agencies and to other conservation bodies about worrying declines in population size or reproductive success, with special reference to species on the UK red and amber lists.
This document is the result of the sustained fieldwork of many thousands of the BTO's volunteer supporters. Without their enthusiasm for collecting these hard-won facts, the cause of conservation in the UK would be very much the poorer.The data we present here include information on distributions, from breeding-season and winter atlas projects, and on estimates of the absolute size of breeding populations, which are reported at intervals by the Avian Population Estimates Panel (Stone et al. 1997, Baker et al. 2006). Colonial seabirds, which are well covered by the results of Seabird 2000 (Mitchell et al. 2004) and by the JNCC's Seabird Monitoring Programme, and the majority of species covered by the Rare Breeding Birds Panel (Holling & RBBP 2007b, 2008, 2009, 2010a, 2010b), are not included here. Wintering populations of waterfowl are covered by the Wetland Bird Survey annual reports (e.g. Calbrade et al. 2010) and by the WeBS alerts system (Thaxter et al. 2010).
The main emphasis of this report is on trends in the abundance and demography of individual species. The data on trends in abundance also provide the basis for multi-species indicators of bird population changes (Gregory et al. 2004). Four indicators of trends in breeding birds are part of the UK Government's 18 Biodiversity Indicators, which track the UK's progress towards international targets set by the Convention on Biological Diversity in October 2010. This approach has been extended more widely through a collaboration between EBCC, BirdLife and RSPB to produce pan-European bird indicators.
This report should be cited as: Baillie, S.R., Marchant, J.H., Leech, D.I., Renwick, A.R., Eglington, S.M., Joys, A.C., Noble, D.G., Barimore, C., Conway, G.J., Downie, I.S., Risely, K. & Robinson, R.A. (2012) BirdTrends 2011. BTO Research Report No. 609. BTO, Thetford. http://www.bto.org/birdtrends